Technical Generator light not turning on?

[turbo500]

Hello,
Another surprise today with the 500.

Charged the battery as it had been sitting for a while.
Started her up and initially generator light was showing on dash when it turned off. After a few tries she started and while fiddling with the mixture or throttle the light won’t turn on anymore. Even if I turn it off and leave key turned to ignition.
I adjusted idle screw to get it to turn on but that didn’t do it either.

What could have happened?? I didn’t touch anything other than the idle and mixture screw.

Should I measure something with the multimeter?

Thanks as always

 

[bugsymike]

Assuming a dynamo not an aftermarket alternator, this may give a basic way of testing, I know not identical dynamo and regulator but principle the same .https://www.howacarworks.com/electrical-systems/testing-a-dynamo-and-checking-output .

 

[Goldnrust]

If the light wont turn on with the ignition on and engine not running, rather than it not switching off, then it less likely to be an issue with the dynamo itself and more likely to be a more general wiring issue.

Could be as simple as the bulb being blown? Or the wire from the dynamo to the bulb being broken?

 

[bugsymike]

Might be worth checking regulator box contacts not sticking also.

 

[turbo500]

Might be worth checking regulator box contacts not sticking also.

If the light wont turn on with the ignition on and engine not running, rather than it not switching off, then it less likely to be an issue with the dynamo itself and more likely to be a more general wiring issue.

Could be as simple as the bulb being blown? Or the wire from the dynamo to the bulb being broken?

I think I can see the middle cable that goes to the regulator box that is holding on by maybe 2 strands...I will start there. Thank you.